Process for treating fats and fatty oils



Aug. 28, 1945. H. D. ALLEN ET AL 2,383,579

PROCESS FOR TREATING FATS AND FATTY OILS Filed March 30, 1943 STEAM COOLING WATER PRESSU RE CONTROL PREHEATER CONDENSER REACTION COIL ALCOHOL FLAS H CHAMBER STEAM ALCOHOL (CAUSTIC SODA) ACID MXXING CHAMBER ESTERS SALT FILTER I INVENTORS HAROLD DWAINE ALLE N WILLIAM ASHLEY KLI NE ATTORNE Patented Aug. 28, 1945 2,383,579 raoonss FOR 'rarg go FATS AND FATTY Harold Dwaine Allen, Glen Rock, and William Ashley Kline, Morris Plains, N. J assignors to Colgate-Palmolive-Peet Company, Jersey City, N. J a corporation of Delaware Application March 30, 1943, Serial No. 481,080

18 Claims.

the alcoholysis of fatty materials and, more particularly, to animprovedhigh temperature proc ess for reacting fatty glycerides with alcohols, whereby fatty acid esters and glycerine are produced in a relatively short time.

The methods of alcoholysis or radical interchange between a glyceride and an alcohol described by the prior art have had certain disadvantages, especially in continuous operation. Thus, the time required for a reaction between the alcohol and the fatty glyceride to provide satisfactory yields of fatty ester and glycerine on an industrial scale varied in the case of alkaline alcoholysis from about twenty minutes toseveral hours and usually ran about thirty minutes to an hour, and when using an acidic catalyst varled from about three hours to about twenty hours. This not only tied up equipment and stock-in process but, in operating continuously by passing the reactants together through a reaction coil, it was necessary to provide a reaction coil of relatively great length if satisfactory yields were to be produced.

It is an object of the present invention to provide an improved process for reacting fatty glycerides (or other fatty acid ester of a higher alcohol) with an alcohol to produce fatty esters and glycerine (or other higher alcohol) in high yield in a relatively short time.

It is also an object of the invention to provide a novel continuous process for producing a high yield of fatty esters and glycerine from fats and fatty oils in relatively inexpensive and spaceconserving equipment.

Other objects and advantages of the invention will be apparent from the following description, taken in conjunction with the accompanying drawing, wherein:

The figure represents a flow diagram illustrating the flow of materials in the operative steps of a process in accordance with this invention.

According to the present invention, a fatty acid ester of a higher'alcohol (e. g., a glyceride) is contacted with an alcohol, preferably in the presence of an alcoholysis catalyst. The mixture is heated to a temperature above the normal boiling point of the alcohol, and a pressure sufflcient to preserve a liquid alcohol phase is maintained. A very rapid reaction takes place, with formation of alkyl esters and the higher alcohol (say. glycerine) in a relatively short time. Unreacted alcohol is removed, and the products are separately recovered.

The present invention relates to a proces for completion desired in a single hot contacting of the materials, or, as disclosed by Joseph Henry Percy in United States patent application Serial No. 462,369 (filed October 17, 1942) the glycerides may be partially esterifled with the alcohol in a first treatment to form a pool of partially reacted material containing monoglycerides and diglycerides, so that the reaction mixture is substantially homogeneous. The partial esterification may be accomplished by keeping the glyceride and the alcohol in contact in a pool at moderate or at elevated temperatures for a time interval insumcient for the reaction to go to completion under the operating conditions, as by continuously running fatty glyceride, alcohol and catalyst into a pool or mixing chamber and continuously withdrawing a substantially equivalent amount of partially reacted material at a rate designed to maintain uniform conditions in the pool. The reaction of the constituents of the withdrawn material is then brought toward completion at a temperature above the normal boiling point of the alcohol involved and at a pressure which keeps an alcohol liquid phase. It may be preferred at this point, when using an alkaline catalyst, to add sufficient acid to decompose any soap formed from the catalyst, and in certain cases, especially when alcohols higher than methanol are employed in the process, the appearance of two phases does not occur until after acidification or removal of unreacted alcohol.

While the phases may be separated, with or without acidification, before removal of the excess alcohol, it is generally preferred to vaporize un- The reaction may be brought to the degree of 55 reacted alcohol prior to settling, as disclosed by Walter Russell Trent in United States patent application Ser. No. 462,370 (filed October 1'7, 1942) After removal of the alcohol, the residue is allowed to settle; glycerine separates out as a lower layer and is withdrawn, and the upper layer containing alkyl esters, and in some cases incompletely reacted glycerides, is also removed for further processing. Various ways of treating the upper layer, which comprises the esterifled material, have been pointed out in application Ser. No. 462,369.

In one procedure in accordance with the present process, the fatty glyceride is premixed with an alcohol and a catalyst and is passed through a contactor coil. There the mixture is heated to a temperature above the boiling point of the alcohol but below its critical temperature and below the temperature of substantial degradation of the materials. Sufficient back pressure is applied to maintain a substantial proportion of the alcohol phase.

in thellquid state. The mixture remains in the contactor coil for a relatively short time, say of the order of up to about ten minutes for alkaline alcoholysis and up to about thirty minutes when using an acidic catalyst, and is then run to a preheater, where it is heated under substantially atmospheric pressure to a temperature sufiicient to volatilize the excess alcohol. The resulting liquid-vapor mixture is passed into a separating chamber from which the volatilized unreacted alcohol is withdrawn and preferably passed to a condenser and receiver. The remaining material comprises alkyl esters and glycerine, which are separately recovered. This may be accomplished by codistillation and settling the distillate or by running'the material directly into a settling tank. The glycerine separates out as a lower layer and is withdrawn, and the esters (and glycerides, if

present) are also removed. The process or any step thereof may be carried out in batch, intermittent orcontinuous operation.

In general, the fatty oil,.,alcohol and catalyst maybe premixed in a homogenizer at about room temperature before being run into the reaction coil. When carrying out the alcoholysis with an alkaline catalyst, it is preferred thusto mix the reactants at a moderate-temperature if small amounts of water are present, in order to avoid the possibility of excessive local saponification of the resulting esters. Such saponification removes the catalyst from the reaction body before the reactants have been thoroughly mixed and al lowed'to react. When using an acid catalyst or when, even with an alkaline catalyst, the reactants are substantially anhydrous, the oil and the alcohol may be separately preheated to the desired reaction temperature and thoroughly mixed directly in the reaction coil, whereby the reaction can be completed in an extremely short reaction time. In the presence of an alkaline catalyst andJof-small amounts of water, preheating and hot contacting tend to decrease the yield of esters,

The reaction coil is heated to provide tempera- 'tures above the boiling point of the alcohol at atmospheric pressure, say to a temperature of about 80 C. to about 160 C. or higher, but below the temperature of substantial degradation of the materials. Where an alkaline catalyst is employed, this may also be below the temperature of substantially complete removal of the alkaline catalyst by saponification of the resulting esters. However, a. temperature may be employed which will produce high ester and glycerine yields in a very short and practical reaction time with simultaneous conversion of the alkaline catalyst to soap. This yield will be a maximum at a particular temperature for a given combination of reactants. In acid or alkaline alcoholysis with either methanol or ethanol, it is preferred to maintain temperatures of about 80 C. to about 160 C., and temperatures of about 90 C. to about 130 C. have given particularly satisfactory results.

The mixture in the reaction coil is kept under a pressure suflicient to maintain a liquid alcohol If desired, the pressure may be low enough to permit the volatilization of a portion of the alcohol during the reaction, but, in general, efliciency of operation is improved when the amount of alcohol volatilized in the coil is relatively low- Thus, at a reaction temperature of 100 C. for methanol, it is preferred to employ a gauge pressure of 55 pounds per square inch or higher, say about '75 pounds per square inch, whereby the alcohol is substantially unvaporized.

- hol and especially methanol.

A similar pressure is applied in ethanolysis at 0., although at this temperature an even lower pressure would'keep substantially all of the ethyl alcohol in the liquid state. As the reaction temperature rises, higher pressures are required, a suitable pressure for reaction with methanol at about C. being of the order of pounds per square inch absolute.

The reaction mixture leaves the coil and, if necessary, may then be heated to volatilize the excess alcohol, with or without prior neutralization. Where the reaction mixture contains unconverted catalyst and is not neutralized before volatilizing the excess alcohol, it is advantageous to carry out such volatilization below the temperature of substantial reversal of the reaction upon removal of the alcohol. In general, the operation may be carriedout at reduced pressures, at atmospheric pressure, or at supertamospheric pressures.

The fatty material treated by the process may be any of the natural fatty acid esters, such as the fats and fatty oils suitable for employment by the soap-makingart in any of the processes heretofore known, or any other fatty acid ester of a higher alcohol, such as glycerol or other polyhydric alcohols or long-chain (say, about twelve to about twenty carbons) monohydric alcohols,

ormixtures'of these esters, especially glycerides is preferably employed, as the presence of water decreases the yield of esters in alkaline alcoholysis and slows down the reaction when an acid catalyst is used, small amounts of water can be tolerated when, carrying out the reaction with the lower alcohols, such as methyl or ethyl alco- Similarly, Where acid alcoholysis is employed or where, in alkaline alcoholysis, acidification of the reaction mixture, is contemplated, either before or after volatilize.- tion of the unreacted alcohol, free fatty acid may be present in the glyceride in the proportion of 10% to 20% or even higher.

In carrying out the alcoholysis according to this invention, short-chain aliphatic monohydric alcohols, including aryl-substituted aliphatic al- I cohols, are preferably employed, particularly the saturated, primary alcohols, especiallyalcohols having a boiling point in the presence of water in excess of the azeotropic composition of lower than 100 C. at atmospheric pressure and, more particularly, the lower alcohols having one to about six carbon atoms per molecule. Thus, alcohols satisfactory for use in forming esters with the fatty acid components of the glycerides treated include such low molecular weight monohydric alcohols as methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, secondary butyl alcohol, tertiary butyl alcohol, the amyl alcohols, benzyl alcohol, etc. While any proportion of fatty material and alcohol may be used, it is preferred to employ an amount of alcohol at least about 50% in excess of the calculated theoretical amount necessary for alcoholysis of the particular glycerides treat ed, and particularly satisfactory results have been I or anacidic catalyst may be employed. vAmong those which have been found suitablefor use in the present process are sodium hydroxide, sodium methylate, sodium carbonate, barium oxide, lime, tetramethyl ammonium hydroxide, boron trifiuoride, aluminum chloride, hydrochloric acid, trichloracetic acid, phosphoric acid, glycerine monoacid sulphate, sulphuric acid, organic sulphonic acids, alkyl sulphuric acids, etc. Whileit is possible to obtain good yields with proportions of catalyst up to about 0.30 mol per equivalent of fatty glycerides and higher, it is preferred to use large excesses. of alcohol and to introduce relatively small amounts of catalysts, say of the order of about 0.03 mol to about 0.10 mol per equivalent of glycerides. A convenient way of introducing the catalyst into the reaction mixture is in admixture with and, where practical, advantageously in solution in the alcohol employed. In alkaline alcoholysis, when the glyceride treated contains free fatty acid, sufiicient alkalinecatalyst is added to provide an excess of alkali above that destroyed by the free fatty acid present.

ing a large proportion of free fatty acids, as the Example I About 224 c. e. per minute of refined anhydrous coconut oil is pumped to a homogenizer and is there contacted with 96 c. 0. per minute of anhydrous ethyl alcohol containing 0.7 5% of sodium hydroxide. The materials are thoroughly mixed in the homogenizer, and the mixture is run into a reaction coil having a holding time of approximately ten minutes. The coil is jacketed with low pressure steam at a temperature of about 100 C. and is equipped with means for maintaining a back pressure upon the contents thereof. The reaction mixture is kept under a pressure of about 90 pounds per square inch absolute and is run from the reaction coil at a temperature of about 100 C. The mixture is passed with reduction in pressure through a preheater, which is also steam jacketed, and the temperature of the mixture is there raised to 110 C. The ethyl alcohol is vaporized within the preheater pipe, and the liquid-vapor mixture is run into a packed column for separation of the vapor. A series of steam coils is located at the bottom of the column and serves as a reboiler. The ethyl alcohol is removed at the top of the column toa condenser and receivers, and the ethyl esters of coconut oil acids, glycerine and any soap present drop through the series of steam coils into a settling chamber. Glycerine separates out in the lower layer, which is withdrawn, and theupper layer.

comprising the ethyl esters is removed for purification and further processing.

Example II About 285. parts by weight per minute of substantially anhydrous cottonseed oil is mixed with 160 parts per minute of substantially anhydrous methanol and 1.6 parts per minute of sodium hydroxide (about 0.04 mol of sodium hydroxide per equivalent of oil) during a period of 4.1 minutes. After thorough mixing, the materials are into a reaction coil, where they are heated to between 101 C. and 103 C." A sufiicient back pressure is maintained upon the coil to prevent volatilization of the alcohol. The coil is equipped with outlet cocks at various points therealong for the purpose of withdrawing'the material after any desired interval of reaction time. After 3.1 minutes in the coil, a portion of the reaction mixture is withdrawn-and promptly acidified with dilute sulphuric acid to halt the reaction. The acidified mixture is allowed to settle, and a'lower glycerine layer is withdrawn. The upper layer is washed with water to remove unreacted alcohol, residual glycerine and excess mineral acid, and it is then dried and vacuum distilled. An ester. yield of approximately 96.2% of the calculated theoretical yield is obtained.

A second portion of the reaction mixture is removed from the reaction coil after an additional 4.1 minutes and is treated in a manner similar to the treatment of the first portion. A yield of methyl esters equivalent to about 96.5% of the calculated theoretical yield is obtained.

Example III 1 Using the same proportions of cottonseed oil,

About parts by weight of coconut oil are charged into a stainless steel bomb with 72 parts of methyl alcohol and 1 part of concentrated sulphuric acid. The bomb is brought to a temperature of C. and maintained at approximately that temperature for some forty-five minutes with intermittent shaking. It is then cooled to about 25 C., and its contents are washed with water, dried and filtered. Theyield of distillable material obtained, comprising methyl esters of the coconut oil fatty acids, is about 97.3% of the calculated theoretical yield.

Example V Employing the same equipment and procedure as in Example IV, 285 parts by weight of No. 4 tallow containing about 14% of free fatty acids are charged into a bomb with 160 parts of methyl alcohol and about 3 parts of concentrated sulphuric acid. After forty-five minutes at a temperature of about 135 C. and removal of excess alcohol, a yield approximately 96.4% of the calculated theoretical is obtained.

Example VI A substantially anhydrous mixture of coconut oil and ethyl alcohol in approximately equal parts by weight is heated to about 130 C. under sufiicient pressure to keep the alcohol in the liquid phase. The mixture is passed into a stainless steel homogenizer at a rate of about 200 parts by weight per minute and is contacted there with about 1' part per minute of concentrated sulphuric acid, meanwhile maintaining the pressure. The materials are thoroughly mixed at C. for about four minutes, and the efiiuent is run into a steam-jacketed reaction coil having a holding time of approximately five minutes.

The temperature is kept at about 140 C. and a back pressure of 165 pounds per square inch assolute is maintained within the coil. The reaction mixture is flashed into a vaporization chamber maintained at 135 C.,' and excess ethyl alcohol is volatilized and removed. The remainder of the mixture is passed into a settling tank, from which glycerine and ethyl esters are separately withdrawn.

Example VII About 215 parts by weight per minute of coconut oil are run into a homogenizer and are there mixed with about 230 parts per minute of ethyl alcohol containing about 0.6% of sodium hydroxide. The materials are thoroughly mixed for about three minutes, and the mixture is run into a heated reaction coil of such dimensions as to be able to contain 3,200 parts of material, that is, having a holding time of about seven minutes at the present rate of feed. The materials are heated therein to about 100 C. and are maintained under a back pressure of about 90 pounds per square inch absolute. The'efiiuent from the reaction coil is run. into a preheater at substantially atmospheric pressure and it is there heated to about 110 C. Unreacted ethyl alcohol is vaporized, and the liquid-vapor mixture is passed to a packed column which is situated over a series of steam coils. The steam coils serve as a reboiler, and steam is furnished to them at a pressure sufiicient to provide an outside surface temperature of about 130 C. vaporized unreacted alcohol is withdrawn at the top of the column and is condensed and stored for reuse in the process. The residue flows through the reboiler and into ar acidification tank, where sufiicient sulphuric acid is added to provide an acidic reaction mixture having a pH of about 4.0. The acidified mixture is then settled, and a lower glycerine layer is removed. The upper layer comprising the ethyl esters of coconut oil acids overflows through an outlet in the upper portion of the settling tank.

Example VIII About 285 parts by weight per minute of cottonseed oil are thoroughly mixed with about 160 parts per minute of methyl alcohol and about 1.6 parts per minute of sodium hydroxide for a period of about thirty seconds, the reactants being at about C. throughout. The mixture is then run into a reaction coil having a holding time of about thirty seconds and the temperature is raised to about 130 C. Suiilcient pressure is maintained within the coil to keep methyl alcohol in the liquid state. The efliuent from the coil is flashed into a vaporization chamber at atmospheric pressure and then into a second chamber under a vacuum of about 26 inches of mercury, and excess methanol is volatilized and withdrawn. The residue flows into a settling tank, where a lower glycerine-containing layer is withdrawn. The upper layer is removed, washed, dried, and vacuum distilled, and a yield of methyl esters of cottonseed oil equivalent to about 97.0% of the calculated theoretical yield is obtained.

Example IX A dry mixture of about 80% tallow to about 20% coconut oil is preheated to about 73 C. and is pumped into a reaction coil at a rate of about 785 parts by volume per minute. Substantially anhydrous methanol at about 22 C. is pumped into the coil at a rate of about 500 parts by volume per minute. The oil mixture and the alcohol run through the pump together and are mixed therein during a period of about six seconds. The alcohol contains about 0.75% anhydrous caustic soda based on the oil used. The reaction mixture in the coil is heated to about 123 C. and is under a gauge pressure therein of about 125 pounds per square inch. The coil has a holding time of about thirty-seven seconds at the present throughput rate, and at the end of this period the eiliuent at about 123 C. is flashed into a vaporization chamber maintained at about 129 C. and atmospheric pressure. The excess methanol is volatilized, and the residue is passed to an acidification and settling tank, where it is acidified, washed, dried and distilled. A yield of esters equivalent to about 97.5% of the calculated theoretical yield is obtained.

Example X A substantially anhydrous mixture of coconut oil and tallow in the proportion of about 1 to 4 is heated to about C. and run at about 785 parts by volume per minute directly into a reaction coil having a capacity of about 785 parts by volume. Substantially anhydrous methyl alcohol containing about 0.75% anhydrous caustic soda on the basis of oil used is also run directly into the coil at a rate of about 500 parts by volume per minute. are heated to about 123 C. under a pressure of 125 pounds per square inch gauge during the period of 0.61 minute when they are passing therethrough. The efliuent passes through a solution heater at atmospheric pressure and is vaporized in a flash chamber at C. Excess methyl alcohol is volatilized, and the residue is treated as in Example IX, a yield of esters equivalent to about 97.5% of the calculated theoretical yield being recovered.

Example X I A substantially anhydrous mixture of tallow and coconut oil in'the ratio of 4 to 1 is heated to 113 C. and run to the inlet of a .pump at a rate of about 785 parts by volume per minute. Substantially anhydrous methanol containing 0.75% dry sodium hydroxide on an oil basis is heated under pressure to about 119 C. and run to the same pump inlet at about 500 parts per minute. The capacity of the pump is such that the reactants pass through at these rates in about six seconds. The materials are pumped into a reaction coil, through which they pass in about seventy-eight seconds, and the temperature of the reaction mixture is raised to about 138 C. under a gauge pressure of about 163 pounds per square inch. The effluent from the coil passes into a tube under atmospheric .pressure, where the temperature is reduced to about 133 C., and it is then treated in an atmospheric vaporization chamber at about 129 C., where excess alcohol is volatilized. The residue is treated as in Example IX, and a yield of esters equivalent to about 98% of the calculated theoretical yield is obtained.

Example XII The reactants mix in the coil and v from a supply tank to the mixing chamber. The

fatty oil mixture is pumped to thechamber at the rate of 22.3 pounds per hour, and the alkaline alcohol is pumped into the chamber in confluence therewith at the rate of 10.57 pounds per hour. The mixing chamber is equipped with' twenty motor-driven impeller blades adapted to run at 800 R. P. M., and the temperature of the, mixing chamber is 40 C. Under these conditions in the mixing chamber, the two-phase system reaches a finely-divided state and the reaction is initiated.

The volume of the mixing chamber is such that its holding time is about four minutes, and the efliuent passes into a reaction coil which comprises a series bank of double pipe units, the volume of which is equivalent to about ten minutes reaction time. Low pressure steam is supplied to the outer pipe, which forms an annular jacket for the reaction coil, and a reaction temperature of about 100 C. is thereby maintained. The coil outlet is furnished with a pressure controller which maintains a gauge pressure of about '75 pounds per square inch within the coil. Under these conditions of temperature and pressure, the alcohol is substantially unvolatil- 'ized, and a high yield of methyl esters and glycerine is obtained within the reaction time and with the simultaneous conversion of substantially all of the catalyst to soap.

The reaction mixture flowing from the coil is released to substantially atmospheric pressure within a steam-heated tubular preheater, in which the latent heat of vaporization of steam is added to the vaporizing unreacted alcohol at about 100 C. The liquid-vapor mixture is passed to a steam-heated separation or flash chamber at substantially atmospheric pressure. The vaporized alcohol is withdrawn and is condensed in a tubular condenser as substantially anhydrous alcohol for reuse. The residue after vaporization of the alcohol flows into a settling tank, where it is cooled to about 52 C. and is acidified with dilute sulphuric acid. The acidified mixture is allowed to stand, and two layers are obtained.

The lower layer, comprising glycerine together with the water and salt resulting from acidification of the mixture, is withdrawn. The upper layer, comprising the methyl esters of the tallow and coconut oil fatty acids, the fatty acids made by acid splitting of the soap formed by saponification of the esters with the caustic catalyst, and partially reacted monoand di-glycerides, is also removed. This operation gives about 98% conversion of available fatty acid to methyl esters and about 94% liberation of the available glycerine, based upon the calculated theoretical yields.

The ester fractions obtained according to the present invention, with or without washing and/or subsequent purification, can be employed in many chemical processes and products, as in the paint, perfumery, lubricating oils, medicinals and other fields. They may be used for chemical reductions and in many chemical syntheses and one of their greatest outlets for volume consumption is in the soap-making industry.

Although the present invention has been described with reference to particular embodiments and examples, it will be apparent to those skilled in the art that variations and modifications of this invention can be made and that equivalents can be substituted therefor without departing from the principles and true spirit ,of the invention.

We claim:

' 1. The process which comprises heating a fatty acid ester of an aliphatic polyhydric alcohol with an aliphatic monohydric alcohol having one to about six carbon atoms per molecule in the presence of an alcoholysis catalyst at a temperature above the normal boiling point of said aliphatic monohydric alcohol and at a pressure sufficient to maintain the monohydric alcohol in liquid phase, thereby providing a liquid body containing alkyl esters and polyhydric alcohol; and recovering the alkyl esters and the polyhydric alcohol.

2. The process which comprises heating a fatty glyceride with a monohydric alcohol having one to about six carbon atoms per molecule in the presence of an alcoholysis catalyst at a temperature above the normal boiling point of said alcohol and at a pressure sufflcient to maintain a substantial proportion of said alcohol in a liquid phase, thereby providing a liquid body containing monohydric alcohol esters and glycerine; and separately recovering said esters and glycerine.

3. A process for treating fatty materials which comprises heating a fatty glyceride with a satu-' rated, aliphatic, monohydric alcohol having one to about six carbon atoms per molecule in the presence of an alcoholysis catalyst at a temperature about 80 C. to about 160 C. but above the normal boiling point of the alcohol and at a pressure substantially above the vapor pressure of said alcohol at the temperature employed, thereby providinga liquid body containing alkyl esters and glycerine; and recovering alkyl esters and glycerine from said liquid body.

4. The process as set forth in claim 3 wherein the alcohol employed is methyl alcohol and wherein the alkyl esters produced are methyl esters.

5. The process as set forth in claim 3 wherein the alcohol employed is ethyl alcohol and wherein the alkyl esters produced are ethyl esters.

6. A process for treating fatty materials which comprises heating a fatty glyceride with an excess of a saturated, aliphatic, monohydric alcohol having one to about six carbon atoms per molecule, said excess being about three to about five times the stoichiometric amount of said alcohol required fOr alcoholysis of said glyceride, in the presence of an alcoholysis catalyst in the proportion of about 0.3 mol to about .10 mol of said catalyst per equivalent of glyceride, at a temperature of about C. to about C. but above the normal boiling point of the alcohol and at a pressure substantially above the vapor pressure of said alcohol at the temperature employed, thereby providing a liquid body containing alkyl esters, glycerine and unreacted alcohol; removing unreacted alcohol therefrom; and separately recovering alkyl esters and glycerine,

7. A process for treating fatty materials which comprises mixing a fatty glyceride with a saturated, straight-chain, monohydric alcohol having one to about six carbon atoms per molecule and with an alcoholysis catalyst; heating the mixture at a temperature of about 80 C. to

about 160 C. but above the normal boiling point I of the alcohol and at a pressure substantially above the vapor pressure of said alcohol at the temperature employed, thereby providing a liquid body containing alkyl esters and glycerine; and recovering alkyl esters and glycerine from said liquid body.

8. A process for treating fatty materials which comprises establishing a liquid pool containing a fatty glyceride, a saturated, straight-chain, monohydric alcohol having one to about six carbon atoms per molecule, alkyl esters, glycerine and partially reacted glycerides; continuously introducing a fatty glyceride and a saturated, straight-chain, monohydric alcohol having one to about six carbon atoms per molecule together with an alcoholysis catalyst into said liquid pool; continuously withdrawing a. portion of said liquid pool; regulating the rates ofsaid introduction and said withdrawal with respect to the size of the liquid pool to keep the fatty glyceride and the alcohol in contact in the pool in the presence of the alcoholysis catalyst for a period of time sumcient to provide thorough mixing and insufficient for the reaction to go to completion; heating the withdrawn portion at a temperature above the normal boiling point of the alcohol and at a pressure substantially above the vapor pressure of said alcohol at the temperature employed, thereby providing a liquid body containing alkyl esters and glycerine; and recovering alkyl esters and glycerine from said liquid body.

9. A process for treating fatty materials which comprises heating a fatty glyceride with a saturated, aliphatic, monohydric alcohol having one to about six carbon atoms per molecule in the presence of an alkaline alcoholysis catalyst for up to about ten minutes at a temperature above the normal boiling point of said alcohol and at a pressure substantially above the vapor pressure of said alcohol at the temperature employed, thereby providing a liquid body containing alkyl esters and glycerine; and recovering alkyl esters and glycerine from said liquid body.

10. A process for treating fatty materials which comprises heating a fatty glyceride with an excess of a saturated, straight-chain, monohydric alcohol having one to about six carbon atoms per molecule in the presence of an alkaline alcoholysis catalyst for up to about ten minutes at a temperature of about 80 C. to about 160 C.'but above the normal boiling point of the alcohol and at a pressure substantially above the vapor pressure of said alcohol at the temperature employed, thereby providing a liquid body containing alkyl esters, glycerine and unreacted alcohol; volatilizing unreacted alcohol from said liquid body at a temperature below the temperature of substantial reversal of the reaction upon removal of the alcohol; and recovering alkyl esters and glycerine from said liquid body.

11. A process for treating fatty materials which comprises heating a fatty glyceride with an excess of methyl alcohol in the presence of an alkaline alcoholysis catalyst at a temperature of about 90 C. to about 130 C. and at a pressure substantially above the vapor pressure of methyl alcohol at the temperature employed, thereby providing a liquid body containing methyl esters,

glycerine and unreacted methyl alcohol; removing unreacted methyl alcohol therefrom; and recovering methyl esters and glycerine from said liquid body.

12. A process for treating fatty materials which comprises heating a fatty glyceride with an excess of ethyl alcohol in the presence of an alkaline alcoholysis catalyst at a temperature of about 90 C. to about 130 C. and at a pressure substantially above the vapor pressure of ethyl alcohol at the temperature employed, thereby providing a liquid body containing ethyl esters, glycerine and unreacted ethyl alcohol; removing unreacted ethyl alcohol therefrom; and recovering ethyl esters and glycerlne from said liquid body.

13. A process for treating fatty materials which comprises heating a fatty glyceride with a saturated, aliphatic. monohydric alcohol having one to about six carbon atoms per molecule in the presence of an acidic alcoholysis catalystfor up to about thirty minutes at a temperature above the normal boiling point of said alcohol and at a pressure substantially above the vapor pressure of said alcohol at the temperature employed, thereby providing a liquid body containing alkyl esters and glycerine; and recovering alkyl esters and glycerine from said liquid body.

14. A process for treating fatty materials which comprises heating a fatty glyceride with an excess of a saturated, straight-chain, monohydric alcohol having one to about six carbon atoms per molecule in the presence of an acid alcoholysis catalyst for up to about thirty minutes at a temperature of about C. to about 160 C. but above the normal boiling point of the alcohol and at a pressure substantially above the vapor pressure of said alcohol at the temperature employed, thereby providing a liquid body containing alkyl esters, glycerine andunreacted alcohol; volatilizing unreacted alcohol from said liquid body at a temperature below the temperature of substantial reversal of the reaction upon removal of the alcohol; and recovering alkyl esters and glycerine from said liquid body.

15. A process for treating fatty'materials which comprises heating a fatty glyceride with an excess of methyl alcohol in the presence of an acid alcoholysis catalyst at a temperature of about C. to about C. and at a pressure substantially above the vapor pressure of methyl alcohol at the temperature employed, thereby providing a liquid body containing methyl esters, glycerine and unreacted methyl alcohol; removing unreacted methyl alcohol therefrom; and recovering methyl esters and glycerine from said liquid body.

16. A process for treating fatty materials which comprises heating a fatty glyceride with an excess of ethyl alcohol in the presence of an acid alcoholysis catalyst at a temperature of about 90 C. to about 130 C. and at a pressure substantially above the vapor pressure of ethyl alcohol at the temperature employed, thereby providing a liquid body containing ethyl esters, glycerine and unreacted ethyl alcohol; removing unreacted ethyl alcohol therefrom; and recovering ethyl esters and glycerine from said liquid body.

.17. The process which comprises bringing a stream of fatty material from the class consisting of fats and oils into confluence with a stream of lower aliphatic monohydric alcohol in the presence of an alcoholysis catalyst and under turbulent conditions, subjecting the mixture to a temperature above the normal boiling point of said alcohol and at a pressure suflicient to maintain.

the alcohol in liquid phase whereby alcoholysis of fatty material takes place, introducing the reaction mixture into a zone of lower pressure to volatilize unreacted alcohol therefrom and leave a residue containing glycerine and alkyl esters, and thereafter separately recovering glycerine and alkyl esters from said residue.

18. The continuous alcoholysis process which comprises continuously bringing a stream of fatty material from the class consisting of fats and oils I into confluence with a stream of lower aliphatic monohydric alcohol in the presence of an alcoholysis catalyst and under turbulent conditions. subjecting the mixture to a temperature above continuously withdrawing the volatilized alcohol from said zone, continuously withdrawing the residue from said zone, and separately recovering glycerine and alkyl esters from said withdrawn 5 residue.

HAROLD DWAINE ALLEN. WILLIAM ASHLEY KLINE.

Certificate of Correction Patent No. 2,383,;57 9 August 28, 1945 HAROLD DWAINE ALLEN ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

Page 5, second column, line 53, for about 0.3 mol read about .03 11ml;-

same may conform to the record of the case in the Patent Oflice. Signed and sealed this 6th day of February, A. D. 1951.

THOMAS F. MURPHY,

Assistant Oommz'ssz'oner of Patents. 

